System for harmonic content correction in power electric circuit, system for electric engine control, and cooling compressor

Abstract

The present invention relates to the field of power electronics and electric engines, and describes a harmonic content correction system in power systems. The invention solves the space and weight problem associated with the core of a harmonic content correction inductor, also providing performance advantages of electric engines, such as higher available voltage at full load and higher rotational speed at full load. The invention is particularly useful in refrigeration compressors comprising a switching device my associated with a reactive element.

The invention claimed is: 
     
       1. A system for correcting harmonic current content in an electric power circuit comprising:
 a. at least one rectifier; 
 b. at least one inductor for reducing the harmonic content; 
 c. at least one capacitor; 
 d. at least one switching device associated with the at least one inductor; 
 e. at least one controller associated with the at least one switching device; and 
 f. at least one frequency inverter for electric motor control, wherein the system:
 rectifies the signal from a power source, directs the rectified signal to the at least one capacitor and forwards it to at least one inverter; 
 characterized in that: 
 a signal from the at least one controller activates the at least one switching device, causing the current to divert from the at least one inductor and pass only through the at least one switching device to provide maximum power output, and 
 a signal from the at least one controller disengages the at least one switching device, causing the current to pass through the at least one inductor to provide average power and reduced harmonic current content; 
 wherein the signal received by the at least one controller to activate the switch-on and/or switch-off signal to the at least one switching device, is selected from: over a predetermined time; signaling a thermostat; energizing the system; engine torque; power through the frequency inverter; a signal associated with the start and/or end of the maximum charge cycle of an electric motor or pull down of a refrigerator; 
 wherein the at least one inductor is without current during the pull-down cycle of the refrigerator to provide maximum load rotation to at least one refrigeration compressor. 
 
 
     
     
       2. The system according to  claim 1 , characterized in that the at least one switching device is a relay, a logic switch, a timer, a MOSFET, or a combination thereof. 
     
     
       3. The system according to  claim 1 , characterized in that the refrigeration compressor is a variable capacity compressor.